1. Field of the Invention
The present invention relates to a gas discharge structure for gaseous fuel for leading gaseous furl that has leaked to the outside of a vehicle, should there occur a leakage of gaseous fuel.
2. Description of the Related Art
An automotive vehicle equipped with a fuel gas tank is proposed in, for example, JP-A-0-99544 entitled, xe2x80x9cMOUNTING STRUCTURE FOR A DISTAL END OF A GAS DISCHARGE PIPE FOR COMPRESSED FUEL THAT LEAKS.xe2x80x9d In this automotive vehicle, the fuel gas tank is mounted in the trunk at the rear portion of the vehicle body, the outlet of the gas supply pipe is connected to the fuel gas tank, and the supply port of the gas supply pipe is faced toward the filler recessed portion in the side wall of the vehicle body.
According to this construction, fuel gas can be filled into the fuel gas tank from the supply port of the gas supply pipe.
With this fuel gas tank, it is predicted that fuel gas leaks from the main body of the fuel gas tank and the connecting portion where the gas supply pipe is connected to the fuel gas tank. Due to this, should there occur a leakage of fuel gas, a gas discharge pipe is provided on the automotive vehicle for discharging fuel gas that has leaked to the outside of the vehicle.
This gas discharge pipe is able to discharge fuel gas that has leaked to the outside of the vehicle by making the discharge port face the atmosphere from the filler recessed portion.
Since the filler recessed portion constitutes the side wall of the vehicle body of the automotive vehicle, it is desirable that the configuration of the filler recessed portion be kept small in consideration of the external appearance of the automotive vehicle. To cope with this, two piping systems such as the gas supply pipe and the gas discharge pipe must be mounted within the filler recessed portion whose configuration is so kept small, there is imposed a limitation to the layout of the gas supply pipe and the gas discharge pipe. Therefore, the degree of freedom in designing gas supply pipes and gas discharge pipes is decreased.
To this end, an object of the present invention is to provide a gas discharge structure for gaseous fuel which provides no risk of damaging the external appearance of an automotive vehicle and can increase the degree of freedom in design.
With a view to attaining the object, according to a first aspect of the invention, there is provided a gas discharge structure for gaseous fuel for leading gaseous fuel that has leaked to the outside of a vehicle through a discharge pipe, wherein a discharge port of the discharge pipe is faced toward a space formed below a gap between a roof and a tailgate.
The discharge port of the discharge pipe is faced toward the space formed below the gap between the roof and the tailgate. Since this allows the discharge port of the discharge pipe to be covered with the roof and the tailgate, the discharge port of the discharge pipe can be left invisible from the outside of the vehicle.
In addition to this, since the discharge port of the discharge pipe can be covered with the roof and the tailgate, there is no need to provide on the vehicle body a cover for covering the discharge port of the discharge pipe. Consequently, the limitation to design can be reduced.
According to a second aspect of the invention, there is provided a gas discharge structure for gaseous fuel as set forth in the first aspect of the invention, wherein a distal end of the discharge pipe is protruded a certain distance from a stepped portion constituting a bottom the gap, and wherein a water penetration preventing member is provided at a position spaced apart a certain distance from the distal end.
The distal end of the discharge pipe is protruded over a certain distance from the stepped portion. This allows water flowing over the surface of the stepped portion when it rains or during car washing to be blocked out at the distal end of the discharge pipe. Consequently, it is possible to prevent the ingress of water from the distal end of the discharge pipe.
In addition to this, the water penetration preventing member is provided at the position spaced apart a certain distance from the distal end of the discharge pipe. This allows water entering the space from the gap between the roof and the tailgate to be received by the water penetration preventing member. Consequently, it is possible to prevent water from penetrating from the distal end of the discharge pipe.
According to a third aspect of the invention, there is provided a gas discharge structure for gaseous fuel as set forth in the second aspect of the invention, wherein a water slope is provided on upper surfaces of the stepped portion and the water penetration preventing member.
The water slope is provided on the stepped portion. Consequently, it is possible to ensure that water flows along the surface of the stepped portion, thereby making it possible to prevent water from staying on the upper surface of the water penetration preventing member.
According to a fourth aspect of the invention, there is provided a gas discharge structure for gaseous fuel as set forth in the first aspect of the invention, wherein a water drain pipe is attached to the discharge pipe for draining water that has penetrated into the discharge pipe.
The water drain pipe is attached to the discharge pipe. Should there occur the penetration of water into the discharge pipe, this allows water that has so penetrated to be discharged to the outside through the water drain pipe. Consequently, it is possible to prevent water from staying within the discharge pipe.